For example, in order to form a “T-slot”, in the past, a “T-slot cutter” has been used. A T-cutter is also used for forming an undercut at a side surface of a workpiece. Such a method of forming an undercut on a side surface of a workpiece is, for example, also applied when forming a return flange at a rib of a skin panel of a wing of an aircraft.
A T-cutter has a shank and a head which is joined with a front end of the shank. Usually, the head has cemented carbide tips screwed or soldered to it. There are also T-cutters which have polycrystalline diamond (PCD) tips soldered to their heads.
For example, PLT 1 describes a T-cutter which is provided with a groove part, which extends from an edge part side to a side opposite to the edge parts so as to be inclined in a direction opposite to a rotation direction about an axial center, at an outer circumferential surface of the shank so as to improve the discharge of chips. This T-cutter has cemented carbide throwaway tips screwed to the edge parts.
PLT 2 describes a T-cutter comprised of front end part side tips and proximal end side tips screwed to a cutting head while alternately arranged in a rotational direction of a tool.